1Z0-997-25 Question 136
Select 2Your organization is planning to migrate a critical Oracle 19c Database from on-premises to Oracle Cloud Infrastructure (OCI) with minimal downtime. They have chosen Oracle Zero Downtime Migration (ZDM) to automate most of the migration tasks. Which two steps must you include to ensure a successful and nearly seamless transition?
- A
Lower the source database compatibility to 11g before starting the migration
- B
Manually configure a dedicated Data Guard environment before running ZDM
- C
Run the ZDM pre-check utility to detect and address environment or parameter issues
- D
Use a Data Transfer Appliance to physically ship the entire database to OCI
- E
Perform a switchover from the on-premises database to the OCI database once the logs have fully synchronized
Show answer and explanation
Correct answers: C, E
Explanation
When using Oracle Zero Downtime Migration (ZDM) to move an Oracle Database with minimal downtime, you rely on ZDM� built-in automation and Data Guard replication to keep the source and destination databases in sync. The crucial steps include performing pre-checks (ZDM checks for prerequisites and configuration issues) and executing a clean switchover (which transitions users and applications to the new OCI database once the logs have fully synchronized). Refer to Oracle� ZDM documentation and best practices for detailed guidance on configuring and running migrations with minimal downtime.
- A. Incorrect.
Option 1: Lowering the database compatibility to 11g is not only unnecessary, but it would also cause compatibility issues and is contrary to best practices. ZDM supports modern versions (such as 19c) without needing to downgrade.
- B. Incorrect.
Option 2: While Data Guard is used under the hood by ZDM, you do not need to manually configure or create a dedicated Data Guard environment in advance. ZDM� workflow sets up and manages the Data Guard replica behind the scenes if prerequisites are met.
- C. Correct.
Option 3: Running the ZDM pre-check is essential. It helps identify environment problems, missing software packages, and configuration mismatches before the actual migration. Correcting issues early prevents downtime and ensures a successful migration.
- D. Incorrect.
Option 4: Using a Data Transfer Appliance is typically for one-time, large-volume data transfers in offline or bulk-migration scenarios. This approach is not aligned with minimal downtime goals when Oracle ZDM can continuously sync changes via Data Guard.
- E. Correct.
Option 5: Performing a switchover at the end of the migration process is a key step. After the target database in OCI receives all changes, switching over finalizes the migration, maximizing uptime and minimizing data loss.